When Pat Ford brought his first case to the U.S. Supreme Court in April, focused on whether police need to get a search warrant before examining the contents of a criminal suspect’s cellphone, he knew the court had a range of options in making its decision.

The court could have sided with the state of California, which argued that no search warrant is needed. Or it could have forged a compromise between the two sides.

What Ford got, though, was a unanimous ruling in support of his contention that police must obtain a search warrant from a judge before perusing the contents of an arrestee’s cellphone.

“It was exhilarating. It was kind of surreal to see this unanimous decision making such a big statement on behalf of people’s privacy rights,” said Ford, a Carmel Valley resident and long-time criminal appellate attorney.

“A unanimous decision that benefits criminal defendants is rare in the Supreme Court. It was a big and welcome surprise,” said Ford, who learned of the ruling in late June when he logged onto the Supreme Court’s web site, where decisions are posted.

Thanks to the ruling, police around the country must first obtain a search warrant before examining the contents of a criminal suspect’s cellphone. Legal experts have hailed the ruling as a landmark decision, one that bolsters the view of the Founding Fathers that the Constitution bars unreasonable searches and seizures by the government.

“Modern cellphones are not just another technological convenience. With all they contain and all they may reveal, they hold for many Americans ‘the privacies of life,’ wrote Chief Justice John Roberts for the court. “The fact that technology now allows an individual to carry such information in his hand does not make the information any less worthy of the protection for which the Founders fought. Our answer to the question of what police must do before searching a cellphone seized incident to an arrest is accordingly simple — get a warrant.”

While the ruling is sweeping — and likely applies to other digital devices beyond smartphones — police willingly began to comply with the court’s decision as soon as it was issued.

“It’s definitely a good check and balance for the whole system. It will add a little bit of time to our investigations, but we don’t think it will have a large adverse effect,” said Cmdr. Mike Barletta of the San Diego County Sheriff’s Department investigations division.

“We really are fine complying with the law,” Barletta said.

Deputies in the field can obtain a warrant from a judge over the phone within an hour or so, said Barletta. Information in the phone can be protected from being remotely deleted by placing the phone in a Faraday bag, which shields it from electronic access.

The ruling allows an exception to the search warrant requirement in an emergency, such as a kidnapping when someone’s life might be in immediate danger, Barletta said.

Barletta said he hasn’t heard of any backlash from law enforcement in the weeks since the cellphone ruling was announced. He said it was only a matter of time before such a ruling was made, as technology advanced, increasing the capacity of smartphones to store a wide variety of different types of information.

“With a straight face it was tough to argue against,” Barletta said of the search warrant requirement. “It hasn’t created an undue burden on law enforcement at all.”

Ford served as co-counsel on the case with Jeff Fisher, a professor at Stanford University and one of the country’s foremost Supreme Court litigators. Fisher made the oral arguments before the justices, and Ford sat at the counsel table, and participated in every element of the case.

Ford’s appeal was on behalf of David Leon Riley, a San Diego man convicted in a gang-related shooting. Although no one was hit by the gunfire, Riley received a sentence of 15 years to life due to an enhancement for gang involvement. Photos and videos found on Riley’s cellphone were used against him at the trial.

The U.S. Supreme Court sent Riley’s case back to the California state appeals court, to determine if the evidence gathered illegally from the cellphone — because police did not obtain a search warrant — played a significant role in Riley’s conviction, and if he should be granted a new trial, Ford said.

Ford said the case was close, and that Riley’s first trial ended in a hung jury. He said he believes that if the appeals court does order a new trial and evidence from the cellphone is excluded, Riley would have a better chance of being acquitted.